PROBLEM TO BE SOLVED: To provide a surface-treated powdery material having a high dispersibility to an oil agent, especially to the volatile hydrocarbon oil, having a good product stability, satisfying both of dispersibility and attaching power to skin and excellent in makeup durability.SOLUTION: This surface-treated powdery material is prepared by surface-coating the surface of the powdery material with a dextrin fatty acid ester which is the esterified material of dextrin with a fatty acid, having 3 to 150 average degree of polymerization of the glucose of the dextrin, containing as the fatty acid, 20 to 100 mol% one kind or &ge2 kinds of 12 to 22C branched fatty acid based on the whole concentration of fatty acids and having 1.0 to 3.0 degree of substitution of the fatty acids based on the glucose unit. The fatty acids may contain further 0 to 80 mol% of one kind or &ge2 kinds selected from the group consisting of a 2 to 22C linear saturated fatty acid, 6 to 30C linear or branched unsaturated fatty acid, 6 to 30C cyclic saturated or unsaturated fatty acid and 4 to 11C branched saturated fatty acid, based on the whole concentration of fatty acids.COPYRIGHT: (C)2012,JPO&INPIT【課題】油剤、特に揮発性炭化水素油への分散性が高く、製品安定性が良好であり、分散性と肌への付着力を両立し、化粧持続性に優れた表面処理粉体を提供すること。【解決手段】デキストリンと脂肪酸とのエステル化物であって、デキストリンのグルコースの平均重合度が3~150であり、脂肪酸が炭素数12~22の分岐飽和脂肪酸の1種又は2種以上を全脂肪酸に対して20mol%~100mol%を含有し、グルコース単位当たりの脂肪酸の置換度が1.0~3.0のデキストリン脂肪酸エステルで粉体の表面を被覆処理してなることを特徴とする表面処理粉体。脂肪酸は、さらに、炭素数2~22の直鎖飽和脂肪酸、炭素数6~30の直鎖又は分岐の不飽和脂肪酸、炭素数6~30の環状の飽和又は不飽和脂肪酸及び炭素数4~11の分岐飽和脂肪酸よりなる群から選ばれる1種又は2種以上を全脂肪酸に対して0mol%~80mol%を含有していてもよい。【選択図】なし
